This survey study (n=411) assessed the factors that predict smoking cessation in people who reported quitting or reducing smoking following ayahuasca consumption. Mystical experience and frequency of ayahuasca intake were protective factors, while positive mood (measured by the MEQ30) during the ayahuasca experience was a risk factor. Qualitative analysis revealed eight themes related to the process of smoking cessation/reduction.
Rationale
Smoking-related disease is a major problem globally. Effective smoking cessation treatments are however limited. Increasing evidence suggests that psychedelics have potential as treatments for substance use disorders and may therefore prove an option in aiding smoking cessation.
Objectives
To establish which factors predict smoking cessation in people who reported quitting or reducing smoking following ayahuasca consumption.
Methods
A retrospective cross-sectional mixed-method study (quantitative and qualitative design) was undertaken using data from an online survey evaluating peoples’ experiences before and after drinking ayahuasca. Multivariate logistic regression was performed with smoking condition (cessation or reduction/relapse) as a dependent variable and demographics, smoking, ayahuasca-related variables and the mystical experience (MEQ30) as predicting factors.
Results
A total of 441 responses were grouped according to self-reported smoking status: cessation (n = 305) or reduction/relapse (n = 136) smoking. Logistic regression showed that mystical experience (OR: 1.03; 95% CI [1.00-1.05]) and frequency of ayahuasca intake (OR: 2.16[1.00-4.70]) were protective factors, while positive mood (measured by the MEQ30) during the ayahuasca experience was a risk factor (OR: 0.91[0.85-0.97]). Qualitative thematic analysis identified eight themes (e.g. acquired awareness, spiritual experience, increased motivation) related to the ayahuasca experience and the process of smoking cessation/reduction.
Conclusions
Our results suggest that ayahuasca could be used as a potential tool for smoking cessation and that effects may be mediated by mystical experience. Given the current burden of smoking-related disease and the limited treatment options, studies are needed to investigate the efficacy of psychedelics in smoking cessation.
Papers cited by this study that are also in Blossom
Argento, E., Capler, R., Thomas, G. et al. · Drug and Alcohol Review (2019)
Barbosa, P., Tófoli, L.F., Bogenschutz, M. P. et al. · Frontiers in Psychiatry (2018)
Barrett, F. S., Griffiths, R. R. · Current Topics in Behavioral Neurosciences (2017)
Barrett, F. S., Johnson, M. W., Griffiths, R. R. · Journal of Psychopharmacology (2015)
Tobacco smoking remains a leading global cause of death and disability, and conventional cessation interventions achieve sustained abstinence in only a minority of smokers. Recent clinical and survey evidence has suggested that serotonergic psychedelics can produce sustained reductions in tobacco use for some individuals, potentially via pharmacological effects on neuroplasticity and subjective mechanisms such as insight or mystical-type experiences. Ayahuasca, an Amazonian brew legally used in Brazil in religious and ritual settings, contains DMT plus monoamine oxidase inhibiting beta-carbolines and has been associated in observational work with reductions in substance use and withdrawal symptoms. Daldegan-Bueno and colleagues set out to identify factors associated with self-reported smoking cessation or reduction following ayahuasca consumption in a naturalistic sample. Using a retrospective, cross-sectional mixed-methods design, the study aimed to combine quantitative modelling (including scores on a mystical experience questionnaire) with inductive thematic analysis of free-text accounts to explore which demographic, smoking-related and ayahuasca-related variables predicted quitting versus reduction/relapse.
The study used an anonymous online survey conducted on the LimeSurvey platform between June and July 2018. Recruitment targeted social media and leaders of ayahuasca-using religious groups; the landing page invited people who had 'quit or reduced smoking after one or more ayahuasca experience' to participate. Inclusion required reporting quitting or reducing smoking after ayahuasca; exclusion criteria were age under 18, insufficient Portuguese literacy, prior participation, and history of psychiatric hospitalisation. Participants provided informed consent and the protocol received university ethics approval. Survey content combined closed and open questions on demographics, detailed smoking history (eg age of initiation, cigarettes per day, prior quit attempts, prior treatments), ayahuasca use (eg lifetime frequency, ritual context, intention to quit) and two open questions asking participants to describe the index ayahuasca experience and the cessation/reduction process. Standardised psychometric instruments were embedded: the Questionnaire on Smoking Urges — Brief (QSU-B), adapted to capture craving 6 months before the index experience and at survey completion; the Fagerström Test for Cigarette Dependence (FTCD), administered retrospectively for the 6 months before the index experience; and the 30-item Mystical Experience Questionnaire (MEQ30) with its four validated subscales (mystical, positive mood, transcendence of time/space and ineffability) in the Brazilian adaptation. Qualitative data from the two mandatory open questions (all n = 441 responses) were analysed using an exploratory, inductive semantic thematic analysis. One author coded responses and two co-authors reviewed the final themes; frequencies of respondents endorsing each theme were counted though themes were not mutually exclusive. Quantitative analysis grouped participants into 'cessation' (abstinent since index experience) and 'reduction/relapse' (reduced smoking, temporary cessation or later relapse). Group comparisons used Cramer's V and z-tests for categorical variables and generalised linear models (GZLM) for continuous variables; repeated-measure QSU-B scores were analysed with generalised estimating equations (GEE). A multivariate logistic regression examined predictors of smoking status across three nested models (sociodemographics; smoking and ayahuasca/MEQ30 variables; and a combined model). Bivariate odds ratios were also reported. Post hoc corrections and model-fit criteria (AIC, QIC) guided distributional choices; the cessation group served as reference in regressions.
Of 504 survey completers, 63 were excluded (54 ineligible; 9 inconsistent), leaving a final sample of 441 respondents. Most learned about the survey via social media (81.6%). By self-report, 305 participants (69.2%) reported quitting smoking since their index ayahuasca experience (cessation group) and 136 (30.8%) reported reduction or relapse. The sample had a mean age of 34.2 (± 10.9) years, comprised 52.8% women, and was highly educated (49.7% postgraduate); 71.6% were employed and 61.5% had no children. Participants began smoking on average at 16.29 (± 3.65) years; 59.9% smoked more than ten cigarettes per day and 40.6% had smoked for at least 10 years. Most (78.7%) had attempted quitting previously and 86.6% had not received prior treatment for smoking. Compared with the reduction/relapse group, the cessation group were older on average (p < 0.0001), more often in a relationship (p = 0.0014), more often parents (p < 0.0001), and had smoked for longer, consumed more cigarettes per day (p = 0.0002) and had higher FTCD scores six months prior to the index experience (GZLM group effect W(1) = 5.283, p = 0.0215). Regarding ayahuasca use, mean age at first use was 27.94 (± 9.24) years; 44.6% reported >50 lifetime uses and 39.2% drank ayahuasca fortnightly or more. Most (88.7%) had not attended their index ritual with the explicit intention of quitting smoking and 52.4% required more than one ayahuasca experience to change smoking. Ritual contexts included Santo Daime (44.4%), shamanic/neo‑shamanic (39.5%), União do Vegetal (16.8%) and indigenous (9.3%). The cessation group had a later first-use age (p = 0.0062), more lifetime ayahuasca experiences (p = 0.0044), longer time since the index experience (p = 0.0094), greater likelihood of having attended with an intention to quit (p = 0.0368) and required more experiences to stop (p = 0.0119). On craving (QSU-B), GEE analyses showed significant effects of group (W(1) = 24.605, p < 0.0001), time (W(1) = 1480.247, p < 0.0001) and their interaction (W(1) = 112.629, p < 0.0001); post hoc testing indicated higher pre-index craving in the cessation group and a marked reduction by survey completion (p < 0.0001). No between-group differences emerged on the four MEQ30 subscales in univariate tests. Multivariate logistic regression presented three models. In Model 1 (sociodemographics) older age (OR 1.03 per year, 95% CI 1.00–1.06, p = 0.0096) and being in a relationship (p = 0.0085) predicted cessation. Model 2 (smoking and ayahuasca variables) found longer prior smoking history (p = 0.0052), monthly ayahuasca frequency (OR 2.37, 95% CI 1.03–5.45, p = 0.0418), longer time since the index experience (OR 1.68, 95% CI 1.07–2.63, p = 0.0221) and higher total MEQ30 mystical experience score (OR 1.03, 95% CI 1.00–1.06, p = 0.0118) associated with cessation; by contrast the MEQ30 positive mood subscale was inversely associated (OR 0.91, 95% CI 0.85–0.97, p = 0.0070). In the combined Model 3 (best-fitting), being in a relationship (OR 1.81, 95% CI 1.15–2.85, p = 0.0095), frequent ayahuasca use (fortnightly, OR 2.16, 95% CI 1.00–4.70, p = 0.0513) and higher mystical experience scores (OR 1.03, 95% CI 1.00–1.05, p = 0.0240) predicted cessation, while the positive mood subscale again related to lower odds of cessation (OR 0.91, 95% CI 0.85–0.97, p = 0.0095). The frequency of ayahuasca intake emerged as one of the strongest protective factors. Qualitative analysis yielded eight themes from participants' accounts. Themes 1–5 described index-experience characteristics: acquired awareness (insight into smoking causes and self-care), sensorial experiences (aversive imagery, tastes or smells linked to tobacco), purging (physical excretions interpreted as cleansing), spiritual experiences (contact with spiritual entities or healing, awareness of smoking's spiritual impediment), and non‑specific/ineffable experiences. Themes 6–8 related to the cessation process: decreased desire/repulsion to cigarettes, immediate or gradual cessation (some reported effortless abstinence, others struggled), and increased motivation or determination to quit. Many respondents also reported wider positive changes after the index experience, including reduced alcohol (68.3%), reduced other drugs (44.2%) and reduced medication use (19.3%).
Daldegan-Bueno and colleagues interpret their findings as supporting a potential role for ayahuasca-related experiences in facilitating smoking cessation among a self-selected sample. The study team highlight that the cessation group began with a heavier smoking profile yet reported greater reductions in craving and a higher likelihood of sustained abstinence at survey completion. In multivariate models, higher scores on the MEQ30 mystical experience scale and greater frequency of ayahuasca intake predicted cessation even when controlling for sociodemographics and smoking history; unexpectedly, the MEQ30 positive mood subscale was associated with reduced odds of cessation. The authors situate their results alongside prior psilocybin and psychedelic survey literature that links mystical- or insight-type experiences with enduring behavioural change. They propose mechanisms that include both neurobiological effects and subjective processes such as insights, shifts in values and reductions in anxiety or depression. Qualitative themes were consistent with these mechanisms, emphasising increased self-awareness, sensorial aversion to tobacco, purgative experiences and heightened motivation. The paper also notes cultural factors specific to Brazilian ayahuasca use, including the 'peia' concept (a challenging cleansing experience) and ritual settings that may augment expectations and social pressures for behaviour change. Several limitations are acknowledged. The convenience, self-selected sample prevents estimating prevalence and limits generalisability; group assignment relied on self-reported abstinence without biochemical verification; recall bias and the retrospective anchoring to a single 'index' experience may have influenced responses; ritual contexts and membership in organised ayahuasca groups could confound effects through social mechanisms; the study did not assess other forms of tobacco use such as rapé; and multiple comparisons were largely uncorrected, so some reported associations might lose statistical significance after stringent correction. The authors therefore refrain from causal claims and emphasise the need for controlled prospective studies. In terms of implications, the investigators suggest that the observed associations motivate further rigorous research — including randomised or open‑label prospective trials — to evaluate ayahuasca or psychedelic-assisted approaches for tobacco cessation, and to clarify the roles of mystical-type experiences, the positive mood component, and the optimal intensity/frequency of psychedelic exposure.
In this convenience sample of people who attributed smoking reduction or cessation to ayahuasca use, higher mystical-experience scores and more frequent ayahuasca intake were associated with greater odds of quitting, while the positive mood component of the MEQ30 was unexpectedly linked to lower odds. Participants also described broader health-related improvements such as reduced alcohol or drug use and healthier lifestyles. The authors conclude that these findings add to evidence suggesting psychedelics, and ayahuasca in particular, warrant further investigation as potential tools for smoking cessation, and they call for rigorous, controlled studies to test efficacy, evaluate mechanisms and examine dose‑frequency effects, especially given Brazil's unique cultural context and the global burden of tobacco-related disease.
An anonymous survey (no name recorded) was conducted using the LimeSurvey platform (LimeSurvey 2021) from June to July 2018. Recruitment advertisements with a link to the survey were distributed via social media (Facebook, Instagram and Twitter) and direct contact with the heads of ayahuasca using religious groups. Recruitment material included a landing page with a descriptive introductory text illustrated with an image of an ayahuasca brew entitled 'Ayahuasca and Smoking Reduction Survey' [Ayahuasca e Redução de Tabagismo] inviting individuals who had 'quit or reduced smoking after one or more ayahuasca experience' to participate in the study. The stated goal of the survey was to 'analyse experiences of smoking cessation or reduction after ayahuasca use and investigate possible factors associated with it'. Only individuals who reported quitting or reduced smoking after ayahuasca use, even temporarily, were included. The exclusion criteria were being under 18 years of age; not being able to speak, read and write fluently in Portuguese; having previously participated in the research and having a history of psychiatric hospitalisation. Participants had to give their informed consent by checking 'I agree' at the end of the page to join the survey. The Ethics Committee of the University of Campinas approved the study protocol.
Participants were grouped according to self-attributed smoking status: (a) cessation (smoking abstinence since the index ayahuasca experience) and (b) reduction/relapse (reduction in smoking since the experience, or temporary cessation/ reduction in smoking after the experience). Descriptive statistics comprised absolute values and percentages for categorical variables and mean and standard deviation for continuous variables. To assess differences between groups, categorical variables were tested with Cramer's V test followed by a z-test of proportion, and continuous variables were tested with generalised linear models (GZLM) with an unstructured covariance matrix and the distribution that showed the best fit (using AIC criterion). Differences in continuous repeated measures (i.e. QSU scores) were tested with generalised estimated equations (GEE) with an unstructured covariance matrix and the distribution that showed the best fit (QIC criterion), and the post hoc analyses were corrected with the Bonferroni method. Furthermore, a multivariate logistic regression model was conducted using smoking status as an outcome (cessation or reduction/relapse) and covariates based on theoretical models and existing evidence. Bivariate odds ratio (OR) with 95% confidence intervals (CIs) analyses were performed to identify variables associated with the participant's smoking user status. Three models were developed: model 1 with sociodemographic values as independent variables, model 2 with smoking, ayahuasca-related variables and MEQ30 subscale scores as independent variables and model 3 combining the variables from models 1 and 2. For all models, the cessation group was used as the reference.
We collected a self-selected sample of people who either quit or reduced smoking after one or more ayahuasca experiences and attributed this to their smoking cessation/reduction. The cessation group had a worse smoking pattern before the index ayahuasca experience (i.e. the most important experience in quitting/reducing smoking), with higher dependence and smoking urge scores, longer periods of smoking and higher cigarette consumption. Nonetheless, this group showed a lower urge to smoke at the time of the survey. The vast majority of our sample in both groups (> 80%) did not go to the index ayahuasca experience with the intention of quitting or reducing smoking, even though it is common for people to attend ritualistic use of ayahuasca searching for a cure or relief from ailments, including addiction. To assess the factors associated with smoking cessation, we conducted a multivariate logistic regression including sociodemographic, smoking and ayahuasca-related characteristics as independent variables and the group condition (quitting × reduction/relapse) as the dependent variable. It is important to emphasise that, even when controlling for several variables with a multivariate model, the self-selected nature of our sample limits the power to generalise our findings to other populations. The MEQ30 mystical experience subscale score was a significant predictor of smoking cessation when controlling demographic, smoking and ayahuasca use characteristics (OR: 1.03). Psychedelics, such as ayahuasca, are known to induce mystical experiences, which are associated with positive and prolonged changes in mood, altruism and mental health outcomes). In the context of addiction, the mystical experience may facilitate meaningful personal insights and lasting behaviour changes. Furthermore, they may indirectly alleviate psychological symptoms such as anxiety and depression which are often associated with substance misuse and addiction. Such effects were observed in an open-label psilocybin treatment for tobacco addiction. In this study, those who subsequently gave up smoking had higher scores in respect of those who did not, and a negative correlation was found between MEQ30 scores and urine nicotine levels after 12 months. Qualitative interviews from the same trial reported insights into self-identity or smoking behaviour and mystical experiences, such as feelings of interconnectedness and awe that helped change smoking habits and perceptions, as well as diminish smoking desire). In addition, reports from an online survey on smoking cessation show that psychedelic use might strengthen the belief in the ability to quit smoking). The psychological effects, such as insights and awe (emotional response of vast stimulus that requires mental structures accommodations) experiences, are increasingly being studied as an important factor for the therapeutic potential of psychedelics (Bogenschutz and Pommy 2012;. These experiences can be associated with the presence of mystical experiences and with positive outcomes, such as the reduction of depressive symptoms or decreased levels of narcissistic personality disorder. Similarly, the responses to the open questions in our study show increased awareness (or insight) concerning habits, resembling the mystical, ineffable and spiritual experiences (e.g. spiritual healing) during the index experience. In line with our results, a systematic review of qualitative studies on the use of psychedelic treatments, including ayahuasca, for mental disorders reported that participants had insights that resulted in improved self-awareness or understanding of the underlying causes of maladaptive behaviours (including addiction). The review also found altered self-perception (increased self-love and self-care), an expanded emotional spectrum (allowing contact with previously inaccessible emotions) and transcendental (e.g. mystical, religious, or spiritual) experiences. Additionally, participants from our study reported a reduction in craving and increased motivation to quit smoking after the experience, effects that are considered more specific to ayahuasca than to other psychedelics. Such effects are described in the sensorial experiences and purging themes and include ayahuasca-induced reactions often related to tobacco aversive organoleptic properties. Similarly, previous qualitative studies showed that the purgative experiences of releasing psychological burdens occasioned a Number of different respondents who articulated the theme (percentage of total sample, n = 441); themes are not mutually exclusive b 'Force' is a common term used by ayahuasca users to name the ayahuasca effects c 'Cleansing' is a common term used by ayahuasca users to name a process of detoxification or cure, physical and/or spiritual induced by ayahuasca, often accompanied of intense vomiting, sweating and/or diarrhoea by ayahuasca are meaningful and important in respect to the substance use disorder recovery process). While we found the mystical experience to be a protective factor for tobacco smoking in our sample, a study byusing a similar internet survey design found no statistical significance in respect of mystical experience scores and tobacco consumption after a psychedelic experience. In addition to the key difference in sample characteristics (ritualistic ayahuasca users versus a wide range of psychedelics users), two analysis-related factors can account for these differences. First, structural differences within MEQ30 factors, asused the full score of the MEQ30 whereas we used the four-subscale format. Although the optimum factor structure for the MEQ30 is still a matter of debate in the psychedelic field, the Brazilian adaptation that we used has been statistically validated with the four-subscale format. Second, we used a multivariate, in contrast to their univariate analysis, to investigate the mystical experience controlling for other variables. Similarly, our results are not significant when using univariate analysis. Furthermore, we found that the positive mood subscale of the MEQ30, which represents positive aspects of the mystical experience, such as feelings of joy, ecstasy, amazement, peace and tranquillity, to be a risk factor for tobacco smoking (OR: 0.91). Although there is evidence that psychedelics may induce better mood outcomes, we did not expect to find positive mood as a risk factor, considering that participants from a previous openlabel study who quit smoking after psilocybin experiences had increased positive mood parameters scores. However, the authors did not test specific associations between the MEQ30 subscales and tobacco use outcomes). One possible explanation could be that difficult/challenging experiences motivated by inner unresolved issues could lead to greater motivation to make behavioural changes. In this respect, ayahuasca drinkers often undergo difficult experiences that combine psychological suffering and physical distress (diarrhoea, vomiting and sweating), which in Brazil is colloquially called 'peia' (a regional term for a 'beating'). Such experiences are usually interpreted as being beneficial as they promote a 'spiritual' and health cleansing and provide insights into difficult problems. Indeed, we had several qualitative reports of physical/psychological 'cleansing' related to smoking (described in the qualitative 'purge' theme), and most of our sample already wished to stop smoking (> 60%), which could provide a possible psychological baseline conflict. However, it is important to consider the cultural importance and possible expectation of behavioural changes following the 'peia' phenomenon in Brazilian ayahuasca drinkers may have amplified the recall of the non-pleasant aspects of an index experience related to smoking cessation or reduction. Besides the predictive potential of the MEQ30 subscales (either as protective or risk factors), the frequency of ayahuasca intake was the strongest protective factor. People with fortnightly or more frequent ayahuasca use had greater odds (OR: 2.16) of being in the cessation group. Moreover, people in the cessation group drunk more ayahuasca in their lifetime and needed more ayahuasca rituals to stop smoking when compared to the reduction/relapse group, suggesting that the facilitation process of ayahuasca for smoking cessation involves repeated intake, or a 'maintenance dose', rather than a single one. The reports described in the theme 'immediate or gradual smoking cessation' corroborate this hypothesis, since some participants from the reduction/relapse group described returning to smoking during periods when they were not drinking ayahuasca. These findings are consistent with the results obtained byin a study with members of an ayahuasca-based church (UDV); being an active member and the number of ayahuasca rituals in the previous year predicted lower rates of tobacco use disorder. Similarly, a follow-up ayahuasca open-label study on depression found a reduction in symptoms only for a few weeks. The afterglow-a period of elevated/ energetic mood accompanied by freedom from concerns and anxiety and increased mindfulness capacities that occur after a psychedelic intake)-could account for the possible benefits of recurrent ayahuasca intake. Finally, we found that in addition to the impact of ayahuasca intake in the tobacco-use condition, the respondents reported other positive drug-related changes in their life such as lower alcohol and illicit drug consumption and, from the qualitative reports, positive changes in lifestyle including improved diet and physical exercise. These results add to several existing studies that have reported positive changes in drug consumption and health habits attributed to the ayahuasca experience. Limitations of our research include the following. (1) This research does not show the prevalence of nonsmokers within an ayahuasca sample. Our methodology did not permit an evaluation of the prevalence of smoking cessation within the ayahuasca user population, as our sample was specifically composed of people who had quit/ reduced smoking after one or more ayahuasca experiences. (2) Moreover, the self-selected nature of our sample and our objective to evaluate the effects of ayahuasca intake on smoking cessation/reduction means that our sample is naturally biassed and, therefore, generalisations in respect of our results should be made with caution. In addition, the fact that we defined our groups based on self-reports of tobacco abstinence is a major limitation since self-reports can be biassed towards a socially desirable response). (3) Furthermore, several participants had their experience within a formal religious setting, which can influence their smoking habits through social pressure to stop smoking. This difference can be observed by the much higher smoking cessation rates (69%) found in our sample when compared to those found by(38%) with a naturalistic, rather than ritualistic, psychedelic use. However, this effect should be similar between the groups in our study due to a lack of difference in the frequency of ritual attendance. (4) Our results are also susceptible to recall bias, and the fact that we asked participants to pinpoint an index ayahuasca experience that defined smoking cessation/ reduction-when some of them qualitatively described this as happening more gradually-could have affected our results. (5) It is important to acknowledge that we did not correct most of our analysis for multiple comparisons and, if this had been done, some of the results would no longer be statistically significant (e.g. age started smoking). However, we provide the exact p value throughout for correction calculation (e.g. Bonferroni) if desired. (6) Another limitation is the fact that we did not assess other forms of tobacco consumption, such as traditional snuffs ('rapé'), which is common in some ayahuasca rituals and may influence smoking behaviours (e.g. substitution practices). () Finally, due to the high rates of individuals who stopped smoking, our study lacks a large relapse group for comparison. Furthermore, we did not include a control group, both of which could have led to greater insights into factors associated with smoking cessation.
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